During this grant period, we will develop a radio frequency antenna array for optimized magnetic resonance imaging (MRI) of the human breast. Recent MRI technique development has made possible sensitive detection of breast cancer, implant leakage, and other abnormalities, but these techniques require greater signal-to-noise (SNR) than produced by the linear coils currently marketed. The primary technical goal is to produce a 3040% improvement in SNR over existing technology and simultaneous acquisition from both breasts in the time usually required for a single breast. We will design a four channel array for optimum multi-channel or time multiplexed receivers. For single channel systems, we will design optimized, switchable, generalized quadrature coils. In addition, a single channel implementation will provide approximate multi-channel performance for some applications, using narrowband filters. Commercial partnerships will be formed for sale and distribution of products arising from this work, thus creating the potential for shorter imaging times and/or higher resolution images on the 2500 plus MR systems for which the array will be adapted. PROPOSED COMMERCIAL APPLICATION: The development of a high performance breast imaging coil array would open up a new area of application for more than 2,500 clinical MRI systems. If only 20% of these sites purchased these devices, there would be 500 units sold for about $25,000 each, giving an approximate market of $12,500,000. As MRI of the breast becomes more popular, this figure could increase substantially.